Automatically save and load hashed_passwords as a file

[aduverger]

Hi,

First of all thank you for your work on Streamlit-Authenticator, it's a very appreciated module :)

I have a feature request to ease its use. It turns out that once the hashed_passwords are generated with .Hasher.generate, I end up saving it as a txt file and then load it afterwards for the Authenticate method.

It would be easier to add the possibility to automatically save the hashed_passwords as a file (with the .generate method), and load it (with the .Authenticate method).

The workflow would look like this:

names = ['John Smith', 'Rebecca Briggs']
usernames = ['jsmith', 'rbriggs']
passwords = ['123', '456']

hashed_passwords = stauth.Hasher(passwords).generate(folder_path="path_to_folder")

A .key file is then automatically generated at path_to_folder/hashed_passwords1546.key 1546 here is a random number generated when .Hasher.generate() is called.

Then, when you need to use hashed_passwords, you can use the legacy way:

authenticator = stauth.Authenticate(
    names, usernames, 'some_cookie_name',
    'some_signature_key', cookie_expiry_days=30,
    hashed_passwords=hashed_passwords,
)

Or you can alternatively use the saved hashed_passwords1546.key file:

authenticator = stauth.Authenticate(
    names, usernames, 'some_cookie_name', 
    'some_signature_key', cookie_expiry_days=30
    hashed_passwords_path="path_to_folder/hashed_passwords1546.key"
)

I already implemented most of it for my use, so if you think this a good idea, I could raise a PR.

Best regards, Alex

[mkhorasani]

Thank you! I have no immediate plans to implement such a feature, but please feel free to implement and make a pull request if you wish to do so. Cheers.